The Amazonian Rain Forest Called Devils Gardens - Assignment Example

  Because in these regions of the Amazonian rain forest, we can find a large stand of trees consisting of a single species of tree called the Duroia hirsuta, which according to the legend, is cultivated by the evil forest spirit. These “devil’s gardens” are created by the Myrmelachista Schumann, the ants nesting in the stems of D. hirsuta, which kills all the other trees except its host through formic acid ((Frederickson, Greene and Gordon, 495).      

            Allelopathy ((Frederickson, Greene, and Gordon, 495) is the local inhibition of plant growth by another plant by Duroia hirsute. This is also believed to be the cause of the formation of the “devil’s gardens’ as indicated in the previous studies on mutualism between the Duroia hirsute and Myrmelachista schumanni.   

 One testable hypothesis is that the formation of ‘devil’s gardens’ involves ants, independent of allelopathy. Consider this hypothesis here, and fill in this chart with your predictions about damage to cedar saplings, put yes or no in each of the boxes in the table.

 Hypothesis 1: M. schumanni ant defense keeps other plants out of the garden by increasing leaf damage to cedar saplings.

 Null hypothesis; There is no relationship between the presence of ants and the amount of leaf damage to cedar saplings.

6. Actual experimental results allow you to reject hypothesis 2 but do not “prove” hypothesis 1. How did they test whether leaf damage was caused by formic acid?

            First, they did an ant-exclusion experiment to determine whether the selective killing of plants inside the devil’s garden was due to the activity of the M. schumanni or to the allelopathy by the D. hirsuta. Then, through chemical analysis, which proved that the poison glands of M. schumanni contain formic acid, they detected no other compounds. They also treat leaves with formic acid which resulted in induced necrosis on all the leaves they tested.